/* $NetBSD: getfsspecname.c,v 1.8 2018/12/27 21:35:48 alnsn Exp $ */

/* $NetBSD: getfsspecname.c,v 1.8 2018/12/27 21:35:48 alnsn Exp $ */

/*-
* Copyright (c) 2012 The NetBSD Foundation, Inc.
* All rights reserved.
*
* This code is derived from software contributed to The NetBSD Foundation
* by Christos Zoulas.
*
* Redistribution and use in source and binary forms, with or without
* modification, are permitted provided that the following conditions
* are met:
* 1. Redistributions of source code must retain the above copyright
* notice, this list of conditions and the following disclaimer.
* 2. Redistributions in binary form must reproduce the above copyright
* notice, this list of conditions and the following disclaimer in the
* documentation and/or other materials provided with the distribution.
*
* THIS SOFTWARE IS PROVIDED BY THE NETBSD FOUNDATION, INC. AND CONTRIBUTORS
* ``AS IS'' AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED
* TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR
* PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE FOUNDATION OR CONTRIBUTORS
* BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
* CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
* SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
* INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
* CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
* ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
* POSSIBILITY OF SUCH DAMAGE.
*/
#include <sys/cdefs.h>
__RCSID("$NetBSD: getfsspecname.c,v 1.8 2018/12/27 21:35:48 alnsn Exp $");

#include <sys/types.h>
#include <sys/ioctl.h>
#include <sys/sysctl.h>
#include <sys/disk.h>

#include <stdio.h>
#include <vis.h>
#include <string.h>
#include <fstab.h>
#include <fcntl.h>
#include <stdlib.h>
#include <errno.h>
#include <unistd.h>
#include <util.h>

#define COMPAT_DKWEDGE /* To be removed */

const char *
getfsspecname(char *buf, size_t bufsiz, const char *name)
{
static const int mib[] = { CTL_HW, HW_DISKNAMES };
static const unsigned int miblen = __arraycount(mib);
char *drives, *dk, *p;
size_t len;
int fd, savee = errno;
char *vname;

p = drives = vname = NULL;

/*
* If the name starts with "ROOT.", replace it with "/dev/<root_device>",
* where <root_device> is the value of the kern.root_device sysctl. Any
* characters after the special "ROOT." token are appended to the end
* of this path.
*/
if (strncasecmp(name, "ROOT.", 5) == 0 && strchr(name, ':') == NULL) {
static const int mib_root[] = { CTL_KERN, KERN_ROOT_DEVICE };
static const unsigned int mib_rootlen = __arraycount(mib_root);

strlcpy(buf, "/dev/", bufsiz);
len = bufsiz - 5;
if (sysctl(mib_root, mib_rootlen, buf + 5, &len, NULL, 0) == -1) {
savee = errno;
strlcpy(buf, "sysctl kern.root_device failed", bufsiz);
goto out;
}
strlcat(buf, name + 5, bufsiz);
return buf;
}

if (strncasecmp(name, "NAME=", 5) != 0) {
#ifdef COMPAT_DKWEDGE
/*
* We try to open the disk name, and if we fail with EBUSY
* we use the name as the label to find the wedge.
*/
char rbuf[MAXPATHLEN];
if (name[0] == '/') {
if (getdiskrawname(rbuf, sizeof(rbuf), name) != NULL) {
if ((fd = open(rbuf, O_RDONLY)) == -1) {
if (errno == EBUSY) {
name = strrchr(name, '/') + 1;
goto search;
}
} else
close(fd);
}
}
#endif
strlcpy(buf, name, bufsiz);
return buf;
} else
name += 5;

#ifdef COMPAT_DKWEDGE
search:
#endif
vname = malloc(strlen(name) + 1);
if (vname == NULL) {
savee = errno;
strlcpy(buf, "malloc failed", bufsiz);
goto out;
}

strunvis(vname, name);

if (sysctl(mib, miblen, NULL, &len, NULL, 0) == -1) {
savee = errno;
strlcpy(buf, "sysctl hw.disknames failed", bufsiz);
goto out;
}

drives = malloc(len);
if (drives == NULL) {
savee = errno;
strlcpy(buf, "malloc failed", bufsiz);
goto out;
}
if (sysctl(mib, miblen, drives, &len, NULL, 0) == -1) {
savee = errno;
strlcpy(buf, "sysctl hw.disknames failed", bufsiz);
goto out;
}

for (dk = strtok(drives, " "); dk != NULL; dk = strtok(NULL, " ")) {
struct dkwedge_info dkw;
if (strncmp(dk, "dk", 2) != 0)
continue;
fd = opendisk(dk, O_RDONLY, buf, bufsiz, 0);
if (fd == -1)
continue;
if (ioctl(fd, DIOCGWEDGEINFO, &dkw) == -1) {
savee = errno;
snprintf(buf, bufsiz, "%s: getwedgeinfo", dk);
(void)close(fd);
goto out;
}
(void)close(fd);
if (strcmp(vname, (char *)dkw.dkw_wname) == 0) {
p = strstr(buf, "/rdk");
goto good;
}
}
#ifdef COMPAT_DKWEDGE
/* Last ditch effort assuming NAME=label, and label is a disk name */
fd = opendisk(name, O_RDONLY, buf, bufsiz, 0);
if (fd != -1) {
close(fd);
p = strstr(buf, "/r");
goto good;
}
#endif
savee = ESRCH;
snprintf(buf, bufsiz, "no match for `%s'", vname);
out:
buf = NULL;
good:
if (p++ != NULL)
strcpy(p, p + 1);
free(drives);
free(vname);
errno = savee;
return buf;
}